This study explores strategies to expand Korea's top 10 seafood export in the oversea market, with a specific focus on the impact of export concentration. For certain seafood items such as laver, crab, and mackerel, characterized by low export concentration, adopting a focused export expansion strategy is more effective. Conversely, highly concentrated seafood items such as toothfish, cod, pollack, and abalone face high risks in export performance due to their heavy reliance on a small number of key export countries. To ensure export stability, it is advisable to implement a diversified export expansion strategy for these highly concentrated seafood items. In the case of medium-concentration seafood items like tuna, oyster, and flounder, the decision between a concentrated or diversified strategy should be based on their specific export situations. Tailoring strategies to the distinctive market characteristics of each seafood item enables exporters to effectively increase oversea market share, promoting stability and sustained growth in export performance.